Press Releases

The cosmic network feeds early galaxies

UniGE PRESS RELEASE (Octobre 27, 2020)

The first galaxies were formed 200 million years after the birth of the universe. These galaxies accumulated the vast majority of the stars, dust particles and metals they consist of between one and three bil- lion years after the Big Bang, a crucial period for our understanding of how the galaxies were formed. Astronomers from the University of Geneva (UNIGE), based at the Geneva Observatory – together with the ALPINE project’s international consortium of astronomers – have studied 118 galaxies from this period using the ALMA telescope in the highlands of Atacama in Chile. In a total of eight joint articles (four of which were undertaken largely at UNIGE), the astrophysicists suc- ceeded in going back nearly 13 billion years in time to identify the gas and dust composition of the galaxies. Their analyses, featured in the journal Astronomy & Astrophysics, show that early galaxies are mature already, lending support to the existence of a cosmic network capable of supplying them with resources.


 ALMA image of two dusty galaxies

These are two of the galaxies in the early universe that ALMA observed in radio waves. The galaxies are considered more "mature" than "primordial" because they contain large amounts of dust (yellow). ALMA also revealed the gas (red), which is used to measure the obscured star-formation and motions in the galaxies. Credit: B. Saxton NRAO/AUI/NSF, ALMA (ESO/NAOJ/NRAO), ALPINE team
Press release summary video 



This is a joint Press Release with NRAO (USA), CNRS (France), the Universities of Bologna and Padova (Italy), the University of Cambridge and Kavli Institute (UK), the Dawn Centre (Denmark), CalTech (USA), UC Davis (USA), the Keck Foundation (USA), Cornell University (USA), the University of Valparaiso (Chile), IPMU (Japan), NAOJ (Japan), and the Waseda University (Japan).

Complete UniGE press release
USA: NRAO press release (with other illustrations) - summary video
France: CNRS Press release

ALPINE papers in Astronomy & Astrophysics with first authors from UniGE:
Schaerer et al. 10.1051/0004-6361/202037617

Dessauges-Zavadsky et al. 10.1051/0004-6361/202038231
Ginolfi et al. 10.1051/0004-6361/202038284
Fudamoto et al. 10.1051/0004-6361/202038163

ALPINE papers in Astronomy & Astrophysics appearing in the same volume:
Le Fèvre et al.  10.1051/0004-6361/201936965
Béthermin et al. 10.1051/0004-6361/202037649
Cassata et al. 10.1051/0004-6361/202037517
Gruppioni et al. 10.1051/0004-6361/202038487

Contacts: Daniel Schaerer, Miroslava Dessauges-Zavadsky, Pascal Oesch